US657416A - Speed-controller for electric elevators. - Google Patents

Speed-controller for electric elevators. Download PDF

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US657416A
US657416A US65997397A US1897659973A US657416A US 657416 A US657416 A US 657416A US 65997397 A US65997397 A US 65997397A US 1897659973 A US1897659973 A US 1897659973A US 657416 A US657416 A US 657416A
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motor
circuit
armature
resistance
conductor
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US65997397A
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John D Ihlder
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Otis Elevator Co
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Otis Elevator Co
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P7/00Arrangements for regulating or controlling the speed or torque of electric DC motors
    • H02P7/06Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current

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  • My invention relatestof a speed-controller f forelectric elevators, and has for its object to improve thecon'struction and arrangement of parts whereby the speed of the elevator can be controlled; and it consists in the va rious'feature's 9f invention having the general mode of operationsubstantially as hereinafter more particularly set forth.
  • Fig-Lire 1- is a diagrammatic representation of the circuits and devices embodying theinvention.
  • Fig. 2 isa similar diagrammatic representation showing an additional feature of theisvention, including the extra field-coil, as hereisafter explained.
  • armaturecircuit Also included in the armaturecircuit is a potential switchhXillustrated'dia I grammatical y, and while various construe tions can be used I prefer to use a switchsconf my Patent No. 594,879,dated December'7,-l,8 97.” Also arranged in the-circuit is a stop inotion snap-switch G, which may'heof any proper construction, but is preferably based on the general principles of construction, and operation set forth .in my Patent No. 596,512, dated January4, 1898.
  • the brush D of the auxiliary resistance device in connected by a con- (i motor-19 through the armature of the elect-r0 magnetic dash-pot E to the conductor i. it in not deemed necessaryio trace the circuits through these conductors nnder all conditione,"ae they are of a type enhetantially like thet shown in any prior patent No. 560,216, and it is snfficient to that an the switch-a2 A is moved to one side or the other the circult is closed through the motor, so that the armature Will rotate in one or the other direction,. according to the movement of the arm, and the crush D operates automatically out out more or less of the auxiliary resistance, and in cutting this out to also out out more or less of.
  • I provide means for placing; resistance in the armeturecircnit end producing a parallel circuit to the armature, which circuit contains no much resistance that eufieient current will dowthercthrough to canoe the the motor shall work an a incl-or, even when thedescending ItltKllBiHil ion-don the car naior. 10 do tone in mild nrcccntinet provide enxiliarg resistance iii, erre L v-- i M .Auv u o ehnnt nronro fire ercinin or i, motor,
  • 0 represents the extra field-coil, one ter minal of which is connected byconductor 25 to the binding-post H, which is electrically connected to. the bindingpost .11 ofthe shunt field-magnet coil, while the other terminal of the resistance isconnected by conductor 26 to the binding-post H**, and this bindingpostmay. be connected through contacts a and a with the binding-post J when, the ex-,
  • tra field-coil is used alone without the external resistance; but in the present instance I have shown the external resistance P, one.
  • acorn ductor 30' including contacts g g, of them:- t-omatic stop snap-switch G, the contact '9 being connected to include a portion of the external resistance P.
  • the extra field-coil and a portion or the whcleof the external.- resistance circuit is controlled by the automatic stop snap-switch or may be controlled by theoperator-ou the car, and it is evident that other switches may be arranged in the line, so as to enable the circuit to be controlled-as, forins'tance, by the engineer in the motor-room or by a governor 'orfany of the well-known appliances used in counec-v tion with electric elevators for automatically opening and closing the switches.
  • the closing of the automatic stop snapswitch G includes only a portion of the external resistance P, and the total resistance is therefore lower than when the circuit is closed by the main switch, including the whole of the external resistance, and therefore thecurrent flowing through this circuit is larger, resulting in a greater speed reduction of the motor. It will be understood that not only can this extra field coil with or without the external resistance be used in stopping or slowing the motor, but in case there is a heavy load, for instance, it may be used throughout the travel of the elevator, so that it will move at a slower rate of speed than normal.
  • a potential switch F arranged in the armature-circuit, the coil of which is energized by a branch conductor of relatively-high resistance, extending from the conductor 1 to the minus side 4. While the construction of this switch may be varied, the general principle is that when sufficient current flows through the coils to retain the armature in place the switch-lever F is held in contact with the terminal f; but when the potential falls below the normal the armature s released and the switch-lever F engages eontactf', closing the circuit of the armature, thereby causing the machine to stop, and at the same time it will be observed that the shunt field-magnet coil 3 is unbroken, so that the field-magnets remain energized while the armatureis in closed circuit. ltis not deemed necessary to trace this circuit, as it is indicated by a dash superposed upon the other lines and can be readily traced.

Description

Nu. 657,4!6. Patented Sept. 4. I900. J. n. IHLDER.
SPEED CONTROLLER FOR ELECTRIC ELEVATORS.
(Application filed Nov. 27. 1897.) (No Model.) 2 Sheets-Sheet I.
N. c, THE cams PETERS no. wum'uumc WASHINGTD a N0.657,4l6. Patented Sept. 4, was.
- J. D. lHLDER.
SPE ED CONTROLLER FUR ELECTRIC ELEVATORS.
(Application filed Nov. 27, 1897,)
(No Model.) 2 Sheets Sheei 2.
extra fii'lrt, coil 2 nnn Witnesses UNITED STATES PATE T- OFFICE JOHN D.-IHLDER, OF YONKERS, NEW YORIQASSIGNOR, BY MESNE ASSIGN'MENTS, 'TO. THE OTIS ORANGE, JERSEY.
ELEVATOR COMPANY, or EAST.
' SPECIFICATION-forming m orgasm Patent No. 667,416, tha September 4', 190b,
Application fllsdliovemher 27,189'1i j Seris1No. 659,978. (No model-l .Tn (ti/whom it may concern.- a I I Be it known that I, JOHN D: Inn-mm, a sinzen of the United States, residing at Yonkers, in the county of Westchester and State of'New York, have invented certain new and useful 1 Improvements in Speed-Controllers forElectrio Elevators, of which 'the'followingis a nln-oiiication.
My invention relatestof a speed-controller f forelectric elevators, and has for its object to improve thecon'struction and arrangement of parts whereby the speed of the elevator can be controlled; and it consists in the va rious'feature's 9f invention having the general mode of operationsubstantially as hereinafter more particularly set forth.
In the accompanying drawings, Fig-Lire 1- is a diagrammatic representation of the circuits and devices embodying theinvention; and
Fig. 2 isa similar diagrammatic representation showing an additional feature of theisvention, including the extra field-coil, as hereisafter explained. i
.While my invention is adapted more par ticularly for usein connection with electric elevators, it may be applied for other and dif- -'ferent purposes, and the details oi. construc:
tion and arrangement ofarts may be varied to adapt it for different 0 rcumstances without departing from the general features of the invention, and I amthercfore not limited.
be controlled, and-especially to provide means. whereby the speed canbe electrically con-. trolled, so as not to have to depend upon the.
40 brake'. It has been found that when the elevatoris traveling rapidly. and the switch is operated to stop the motor and the brake is applied thec'ar may be caused to stop too quickly,- causing a jolt orjar, which is unpleasant as well as liable to strain the-apparatus, and one of the main objects ofthe pres ent invention is to'provide electrical means for producing a slow speed before the brake is necessarily applied. These means may be arranged in difierent ways, so as to be opervice.
- ated automatically by the usual automatic stop device, thereby slowing the speed ofthe car as it approacheslhe extremes of its movement in the well,;or it may be operated fronr the car by the attendant'at any p0int,as ap proaching'la'ndings or in case ofemergency, and I will1now proceed to describe the prei'er'r'ed embodiment of the invention. j. In the accompanying drawingsl have shown an arrangement of circuitson the general prim" ciples set forth in my Patent' No.L[56jO,216, granted May 19, 1896, in .whichjM-is-the 'armature of an electric motor connected (to op crate the elevator winding-drum'orother de '(Not shown.) I A represep'ts'J-a' shaft which isad'apted to ,be' operated -by-the usual ghand-ropes orother control deviceflfro'm the car, and'co'n nected to this shaft are the usual switches and po io-changerorcurre -it-reverser B. C repre'se'utsa resistance devicecom posed in t'he present instaiiceof aqnu nber ofcon-- tact-plates c c. c". c c 0 6 21 0* 09091:, with 1 intermediate resistance coils between the. plates, exceptht their ex tremities and between. the plates c 0 Connected to operate-with this resistance is a brush- D,,which' is carried on asuitable lever-a'rnfcontrolled in the usual way by mechanism connected with theshaft A andal'so furthercontrolledlin the present instance by an electromagnetic dash-pot E, as
more fnlly'set forth in, the patentaboveres ferred to.
Also included in the armaturecircuit is a potential switchhXillustrated'dia I grammatical y, and while various construe tions can be used I prefer to use a switchsconf my Patent No. 594,879,dated December'7,-l,8 97." Also arranged in the-circuit is a stop inotion snap-switch G, which may'heof any proper construction, but is preferably based on the general principles of construction, and operation set forth .in my Patent No. 596,512, dated January4, 1898. These mechanical features are not-illustrated iii-details of construction, but areindicated diagrammatically 'sl'ifiicient to enable their-operations to be understood by those skilled-inthe art, anditis not deemed necessary to desoribethem in detail.
' On theshaftA orconnec'ted to be operated thereby isanarm-A, carrying contacts aa,
'strudted substantially like that setiorth'in Y connected together and also carrying on an extension of the arm and insulated from the others a contact c and arranged to cooperate with this arm are the contacts a" a a do, these beingtypical only of the ordinary switch and eni'licient to explain the present invention. it Will he noted that the contecie a" and a are electrically connected together, as-are contacts a a and it will further be noted that contact a is in the form of e segment, with its ends extended, so that When the arm A is moved to the right or the left the contact a will bear upon the segmentcontact a after contact a hears upon contact a or a although the arm A can he moved to a position to withdraw contact a from cone and still retain contact with the plates a a the purpose of which will he understood hereinafter. The circnit-revereer 13 is herein typically represented as having two conductingpletes l5 Bhinsnlated from each i3l18i',&11d
arranged around the plates are the brushes,
1) I) b if,
Inorder that the invention may be best understood, the circuits will now be traced,
' it being generally stated that tostart the motor in either direction the shaft A is open ated in one direction or the other from the elevator-car oy ihe nenal control devices, and this closes the circuit throngh theinotor in the proper direction to canoe it to rotate to raise or lower the car, and at the same time the brush D, controlling the auxiliary resistonce 0, is released from mechanical connecti0n,-so that more or less of'the auxiliary resistance is out out, depending upon the current flowing through the motor and controlled in the present instance by the electromagnetic dasl1-pot E, and when the arm A" is moved to its normal position (ohown in thedrawinge) the brush D is mechanically r etorcdvto the position shown, hearing on the contact-plate c, n The lines pins and minus indicate the it'eedi ngcircnit for the motor, and the cnrrent is supposed to enter by the conductor 1-, extending to the binding-poet H, and thence by the conductor 2 through the shunt field-magnet coils 3 of the motor to'the post 11 thence cythe condnctor 4 out to the main line. Branching from con doctor lie the conductor 5, leading" tethe connected contacts of a of the cwitch. The
contacts a a on the opposite end'oi the switch are connected together, end fronlthein a conductor 6 leads to the contect f of the potential switch l While connected to'thc lever F' of the switch normally hearing on said contact is a conductor 7, leading" to crush 11, and from brush b is a conductor 8,1ending to the binding-poet L'Which is connected by conductor 9 to the brush of the arrow tnre, while for-och m is connected by conductor 10 to the binding-post 1', which in. turn is connected by conductor 11 to the brush 1') of rev. b of the revcrser is connected .oto l2, to the electrcr ar -n13: e
2 cemic same, and thence by conductor to the contact-plate c of the auxiliary resistance 0. From this contact-plate lends a conductor 14 to the binding-poet 5, including a series fieldinagnet coil 8, which is connected to the binding-post J, and thence oy conductor 15in connected to the contact-plate o of the auxiliary resistance. Contact-plate a is connected by conductor 16 to the bindingpost J and thence to the second serieefieldnmgnet coil S to binding-post J which is connected by conductor 17 to the contact-plate c of the auxiliary resistnncej The binding'post J" is connected oy conductor 18 to the con'rnctj'" of the potential switch F, which contact is normally open, asindicated. The brush D of the auxiliary resistance device in connected by a con- (i motor-19 through the armature of the elect-r0 magnetic dash-pot E to the conductor i. it in not deemed necessaryio trace the circuits through these conductors nnder all conditione,"ae they are of a type enhetantially like thet shown in any prior patent No. 560,216, and it is snfficient to that an the switch-a2 A is moved to one side or the other the circult is closed through the motor, so that the armature Will rotate in one or the other direction,. according to the movement of the arm, and the crush D operates automatically out out more or less of the auxiliary resistance, and in cutting this out to also out out more or less of. the seriee field-magnet coilsrS S, no that the greatest torque is exerted in starting the motor, and when running; normally and nnder the canal load the brush D will rest upon the contact c and the motor operetc as at true shunt-motor in a manner Well understood. I
in order to control the speed of the motor, as when it approaches; the extremes of its movement or an intermediate landing or otherwise, I provide means for placing; resistance in the armeturecircnit end producing a parallel circuit to the armature, which circuit contains no much resistance that eufieient current will dowthercthrough to canoe the the motor shall work an a incl-or, even when thedescending ItltKllBiHil ion-don the car naior. 10 do tone in mild nrcccntinet provide enxiliarg resistance iii, erre L v-- i M .Auv u o ehnnt nronro lire ercinin or i, motor,
.d in have conn with thindthe snap-switch This latter content g connected by e conductor 23 with too anziil- 'i-ary armature-resistance the other end which in connected by conductor 24; b11361 ling-poet l which in turn is connected i' With conetrccti n motor to slow up and, further, to incdre that v when the arm A is in the position indicated cuit to the armature is closed,-including a resistancc, and at the same time the movement rates of speed I have found :it desirable to 4 means of the'variousswitches may be placed in circuit parallel to the armature. This exautomatically or otherwise to open and close the contact abears on one or the other of the the armature, including the resistance N, by
"cause the motor to slow down without the swam it will be seen that whenthe-au'tomatic stop snap-switch G is closed, as shown in the draw ings, therein a branch or shunt circuit around the armature, including the resistance N, and as this switch is arranged to be operated the circuit when, for instance, the car is trav elingtoo fast or when,'for instance it approaches the. extreme ends of its travel in the well it will be seen' that the'motor will be caused to rotate more slowly whenever this switch is closed, and the speed of the elevator will therefore be lessened and e en brought to rest, depending upon the relations of the resistance-coil N to the armature-circuit. It will also be seen that when the arm A ofthe switch ismoved to a position so that the coutactplate a bears on the segment a while plates or, a there is also tfclosed shunt around which arrangement the operator on the car is enabled to close the shunt at anytime to necessity of breaking the circuit or applying the brakei It will be observed that this auxiliary armature-resistance circuit is closed in the drawings and the circuit of the arma-- tur'e is broken; but as the arm A is moved to the right or the left, closing circuit with the contacts a or a", the shunt resistance-circuit is also closed; but when the arm is moved to the full extent the shuntis opened and the motor operates uud'er'the usual conditions; but to cause it to slow it is only necessary for the operator t-o'tnru the arm :A pnrtiall y toward its normal position sufiic-ient to cause the contact a to bear on the-neg.- ment to without breaking the circuit between the contacts a and a or a, as the case may be,'anil in this way a-branch or parallel cir-' or the arm A toward its normal position at the center allows'brush D to move upward and-include more crises of the resistance (J in series with the armature, and the speed of the motoris' gradually cut down to prevent a sudden stoppage, such as mightpccur if the armature-circuit. were instantly broken and the brakes applied. Y.
While the, arraugement'thus far described I has been found satisfactory in what may be termed light-duty machines, in machines carrying heavy loads and traveling at high control the speed between greater limitsand to limit the current used in the circuit paral lel to the armature as much as possible. This I accompiish by means of what I term an ,extra field-ooil on the motor, which by tra field-coil may-be used alone for this purpose or in connection with an external resistance, which furnishes a convenient means .flgure the generalj circuits of the motor are lettered the same as in Fig. 1.
0 represents the extra field-coil, one ter minal of which is connected byconductor 25 to the binding-post H, which is electrically connected to. the bindingpost .11 ofthe shunt field-magnet coil, while the other terminal of the resistance isconnected by conductor 26 to the binding-post H**, and this bindingpostmay. be connected through contacts a and a with the binding-post J when, the ex-,
tra field-coil is used alone without the external resistance; but in the present instance I have shown the external resistance P, one.
terminal of which is connected by conductor 27 to the binding-post J, while the otherterminal is connected by conductor 28 with contact a and the segment a is connected by a conductor 29 to the binding-post H**. Also connected to this latter binding-post is acorn ductor 30', including contacts g g, of them:- t-omatic stop snap-switch G, the contact '9 being connected to include a portion of the external resistance P. With these connectionsit will be readily uders t-ood that when the automatic stop snap-switch G is operated to close the circuit a portion of the external resistance P is included in the circuit with the extra field-coil O in shunt around the armature, and when the contact a of the arm A bears on the segment a the whole of the external resistance P is included in circuitwith the extra field-coil. For convenience in tracing. them the externalresistauce circuit is shown in dotted lines, while the extra fieldcoil circuit is shown in dot-and-d'ash lines.
It will thus be seen that the extra field-coil and a portion or the whcleof the external.- resistance circuit is controlled by the automatic stop snap-switch or may be controlled by theoperator-ou the car, and it is evident that other switches may be arranged in the line, so as to enable the circuit to be controlled-as, forins'tance, by the engineer in the motor-room or by a governor 'orfany of the well-known appliances used in counec-v tion with electric elevators for automatically opening and closing the switches. When this extra field-circuit and external-resistance circuit are closed, the current flowing therethrough is limited by the sum of these resistances and the electromotive force of thearmature, and this current acts as a brake 'O!l thev armature and at the. same time adds to themagnetization of the field, the connections being such that the extra field-coil al ways assists the primary shunt field-magnet Minding 3, and the speed of the motor is-conseqnently diminished. As shown in the diag ram,the closing of the automatic stop snapswitch G includes only a portion of the external resistance P, and the total resistance is therefore lower than when the circuit is closed by the main switch, including the whole of the external resistance, and therefore thecurrent flowing through this circuit is larger, resulting in a greater speed reduction of the motor. It will be understood that not only can this extra field coil with or without the external resistance be used in stopping or slowing the motor, but in case there is a heavy load, for instance, it may be used throughout the travel of the elevator, so that it will move at a slower rate of speed than normal. Vith these arrangements as herein indicated, which of course may be varied in detail, it will be seen that by properly proportioning the extra field-coil and external resistance with relation to the other parts of the motor the motor can be effectively slowed without breaking the circuit or applying the brakes, and the current flowing through the circuit may be such as to prevent the machine from sending baclrcurrent into the line or acting as a generator, and atthe same time the current flowing through the extra fieldcoil may be suflicient tomagnetize the motor up to saturation, so that the armature of the motor may run at a slow speed without drawing a heavy current from t e supply-circuit. in connection with this arrangement of devices I have shown a potential switch F arranged in the armature-circuit, the coil of which is energized by a branch conductor of relatively-high resistance, extending from the conductor 1 to the minus side 4. While the construction of this switch may be varied, the general principle is that when sufficient current flows through the coils to retain the armature in place the switch-lever F is held in contact with the terminal f; but when the potential falls below the normal the armature s released and the switch-lever F engages eontactf', closing the circuit of the armature, thereby causing the machine to stop, and at the same time it will be observed that the shunt field-magnet coil 3 is unbroken, so that the field-magnets remain energized while the armatureis in closed circuit. ltis not deemed necessary to trace this circuit, as it is indicated by a dash superposed upon the other lines and can be readily traced.
Having thus described the general principles of my invention and 'set forth the preferred embodiments thereof, without. limiting myself to the construction and arrangement illustrated, what I claim isl. The combination with a shunt-wound motor and circuits and connections for controlling the same, of an open shunt around the armature-terminals of ing a resistance device, and means for closing said shunt and including, resistance be tween the armature-terminals, substantially as described.
2. The combination with a motor and do cnits and connections for controlling the same, of a normally-open shunt around the ar1natnreterminals of the motor, and an automatic stop-switch arranged to close the shunt between the armature-terminals to decrease the speed of the motor, substantially as described.
3. The combination with a motor, and circuits and connections for operating the same, of an extra field-coil in shunt around the armature-terminals of the motor arranged to magnetize the motor in the same direction as the shnnt-field,'and means for closing the extra field-coil on the terminals of the armature, substantially as described.
4.. The combination with a motor and circuits and connections for operating the same,
of an extra field-coil in shunt around thearmature-terminals of the motor, an external resistance included in said shunt, and means for closing the shunt on the terminals of the armature, whereby the magnetization of the field is increased and the speed of the motor decreased, substantially as described.
5. The combination with motor and circuits and connections for operating the same,
of a potential switch arranged in the armature-circuit and adapted to interrupt the sup ply-circuit and to close the circuit of the armature upon itself while the shunt field-circuit is excited, substantially as described.
In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.
'9 JOHN D. IHLDER. Witnesses:
E. RIoHENs, F. E. HUBIBELL.
the motor includ-
US65997397A 1897-11-27 1897-11-27 Speed-controller for electric elevators. Expired - Lifetime US657416A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2462120A (en) * 1941-12-15 1949-02-22 Mozzanini Georges Gabriel Speed controlling means for direct current motors
US8282576B2 (en) 2003-09-29 2012-10-09 Sanofi-Aventis Deutschland Gmbh Method and apparatus for an improved sample capture device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2462120A (en) * 1941-12-15 1949-02-22 Mozzanini Georges Gabriel Speed controlling means for direct current motors
US8282576B2 (en) 2003-09-29 2012-10-09 Sanofi-Aventis Deutschland Gmbh Method and apparatus for an improved sample capture device

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